Cognitive Processes PSY 334 Chapter 4 – Perception- Based Knowledge Representation

Two Types of Imagery  Images involving visual properties.  Images involving spatial properties.  Bilateral temporal lobe damage: Difficulty judging color, size, shape. No deficit in mental rotation, image or letter scanning, judgment of relative positions.

Are Images Like Perception?  A series of experiments to compare perception and imagery: Imagining transformations of mental images vs perceived stimuli. Ponzo illusions occurs with imagery. Difficulty with reversible figures – depends on instructions, harder.  MRI plots show same brain activity.

Hierarchical Structure  Images have structure and are decomposed into chunks based on that structure. Reed’s forms. Grouping of items in room.

Cognitive Maps  Two kinds of maps: Route map – indicates places and turns, but not all landmarks. Survey map – shows all relevant portions of space, not just route.  Adults produce survey maps, kids produce route maps.  Survey maps more versatile.

Map Distortions  Which is farther east: San Diego or Reno?  People map wrong guesses because they reason from the positions of the states, not cities.  Relative positions of larger areas are compared, not details.

Translating Verbal Descriptions  Subjects were asked to read passages, rotate themselves and make judgments: Fastest when making above-below judgments, slower with right-left.  Verbal directions (survey or route) are as good as using actual maps.

Remembering Serial Position  Serial position – what comes first and what comes later in a list.  Anchoring – first items are better remembered in sequences.  Hierarchical encoding helps serial recall: Alphabet song